1. Field of the Invention
The present invention relates in general to an engine cooling water circulation system, and more particularly to an engine cooling water circulation system which is constructed to facilitate water charging thereinto.
2. Description of the Prior Art
Some modernized motor vehicles have a very slanted engine room hood causing the front of the engine room to have a limited space. In this type engine room, the arrangement of the engine cooling water circulation system is inevitably so made that a radiator is positioned at generally the same level as the remaining parts of the system, so that water charging to such system takes a relatively long time because of lack of sufficient water head in the system during the charging. This undesired phenomenon becomes more critical when the system has therein a closed loop circuit such as a heater system which comprises a heater core for a passenger room heater, a water inlet hose leading from the engine water jacket to a lower portion of the heater core and a water outlet hose leading from an upper portion of the heater core to a part of the system which part is positioned lower than the portion where the water inlet hose is connected to the engine water jacket. In fact, during the water charging, a "sealed" air chamber remains in the heater core thus disturbing the smooth water charging in the system.